Pump for feeding molten metal



Dec. 15, 1953 A. L. GAGNE PUMP FOR FEEDING MOLTEN METAL Filed March 15,1951 INVENTOR. Arfhur L. Gag/7e 4 TTORNEY Patented ec. 15, 1953 UITEDSTATES PATENT OFFICE PUMP FOR FEEDING MOLTEN METAL Arthur L. Gagne, SanFrancisco, Calif.

Application March 15, 1951, Serial No. 215,836 Z-CIaiIHS. (o1. 22- 70)The present invention relates to a pump for feeding molten metal and hasparticular reference to a pump designed for feeding molten lead orsimilar metal to a casting mold for making strip material and type.

Pumps of this character used heretofore consisted of a cylindricalhousing having means for supporting the same with its lower endsubmerged in a body of molten metal, a side arm having a dischargenozzle above the level of the metal, an intake port in the side of thehousing and comparatively near the level of the metal, with a floatvalve controlling the intake, and a piston or plunger reciprocable inthe housing for drawing in metal on the upward stroke and for forcingmetal through the nozzle on the downward stroke.

This arrangement had a number of disadvantages.

In the first place, the piston on the upward stroke would not clear theintake port until it approached the limit of its travel and the interimwould create a vacuum sucking on the discharge port and causingundesirable fluctuations in the latter.

In the second place, the pump would draw on the molten metalcomparatively near the top surface and would frequently entrain drossformed on the surface and deposit the same along the pump walls, theplunger and the discharge,

causing undue wear on piston and pump body and the leading of the molds,and calling for frequent cleaning of the elements affected.

In the third place, the suction on the exhaust side and the drossing ofthe metal would frequently result in an uneven flow of the metal.

In the fourth place, the drawing of the molten metal from near the topsurface of the metal body would encourage the forming of dross on saidsurface resulting in loss of valuable tin and antimony.

And finally, the pump drawing from near the surface of the body of metalwould fail to take advantage of the fact that the metal is hottest andbest adapted for pumping near the bottom of the pot where the heat isapplied.

In the present invention it is proposed to provide for a relativelysimple improvement in the pump consisting principally in the placing ofthe intake valve in the bottom end of thepump thereby eliminating or atleast greatly reducing the injurious results of the undesirable featurespointed out, my new pump being designed to draw dross-free metal fromthe bottom of the pot, to insure uniformity of metal flow, to re- 2 ducethe forming of dross on the surface of the body of metal, and to greatlyreduce the entraining of dross into the pumped metal, thereby savingwear on the pump body, the plunger and the nozzle, and essentiallypreventing the leading of the mold.

It is further proposed to provide a suitable check valve at the outletof the pump to prevent the lead previously discharged into the side armfrom flowing back into the pump chamber on the suction stroke.

Further objects and advantages of my invention will appear as thespecification proceeds, and the novel features of. my invention will befully defined in the claims attached hereto.

The preferred form of my invention is illustrated in the accompanyingdrawing, in which Figure 1 shows a side view of my pump in position withrespect to a pot of molten lead,

Figure 2., a plan view of my intake valve assembly used at the bottomend of the pump hous r Figure 3, a side view of the same,

Figure 4, a side view of a plunger used in my pump, taken at a rightangle to that of Figure 1,

Figure 5, a horizontal section taken along line 55- of Figure 1, and

Figure 6, a vertical section through the nozzle used in my pump.

While I have shown only the preferred form of my invention, I wish tohave it understood that various changes and modifications may be madewithin the scope of the claims attached hereto without departing fromthe spirit of the invention.

Referring to the drawing in detail, my pump comprises in its principalfeatures a substantially cylindrical housing I having an inclined arm 2projecting therefrom, with a discharge nozzle 3 at the upper end of thearm, and having an intake valve 4 at the bottom end thereof, and aplunger 5 reciprocable in the lower end of the cylinder and having aplunger rod 6.

The housing l is substantially cylindrical in form and has a slightlyenlarged bottom end i to form a pump chamber 8. The lower end of thechamber is closed by a plug 9 threaded into the cylinder, and the valve4 is threaded into the plug centrally, the valve having a lower axialport I B and an upper port I l of slightly larger diameter, the upperport communicating with the lower port and forming a spherically roundedvalve seat I? therewith. A ball valve I3 is seated on the seat and islimited in its upward movement by a cross-pin 14 extending dia- 3metrically through the threaded portion of the valve.

The arm 2 extends sidewise from the pump chamber 8 in an upwardlyinclined direction and carries at its upper end the nozzle 3 adapted fordischarge into the mold if: indicated only sketchily. The arm has a port2 communicating with the pump chamber and the nozzle.

The housing I, above the pump chamber, is slightly reduced in diameter,as at E6, to serve as a guide for the plunger 5, then widens again, asat [7, to form two oppositely disposed windows 18, and above thewindows, is provided with two lateral brackets 19, by means of which thehousing may be supported with respect to a pot [9' so that the lower endof the housing is submerged in a molten body of lead provided in thepot. The latter is heated from below by means not shown.

Above the brackets, the housing is formed with opposing fiat faces 28providing upper and lower lips or abutments 2| adapted for cooperationwith an operating element in imparting a slight vibratory motion to thehousing as a whole in accordance with conventional practice. The upperabutments 2| have a cylindrical top piece 22 secured thereon, this toppiece having two opposing vertical arms 23 serving as guides for part orthe plunger rod.

The plunger rod with its plunger 5 is illustrated in detail in Figure 4and is of conventional type. The rod is of sufiicient length to projectoutside the housing when the plunger reciprocates in the pump chamberand is provided, at its upper end, with a handle 2 The rod has threeregistering sets of wings 25, 26 and 27, the lower wings serving asguide means within the housing and the two upper sets serving asabutments for operating levers 28 to work against. Between the two uppersets of wings the plunger rod has a pair of transverse wings 29 servingas guide means between the two arms 23.

The general structure of the housing and the plunger is substantiallyconventional, and the principal novel feature of the present inventionlies in the arrangement of the intake valve at the bottom end of thehousing which allows the pump to draw on the lower level of the moltenmetal, where it is most liquid due to the application of heat from thebottom and where it is clear of dross, with the further advantages thatthe pump chamber is full of liquid metal at all times, resulting in asmoother and more uniform flow, that less dross is formed on the surfaceof the metal due to reduced agitation and that no dross enters the pumpchamber or the discharge.

It is apparent that the valve at the bottom should be made or" the bestmaterial available, preferable specially treated alloy steel, hardenedto withstand the heat of the metal in the pot.

As a further feature of the invention I provide a check valve 30 in thelower end of the port 2, this valve being substantially similar to theintake valve 4 and serving to prevent back flow of the molten lead fromthe port 2' into the pump cylinder on the suction stroke.

The nozzle 3 is formed with an adjustable vent as disclosed in detail inFigure 6. The main port 3| of the nozzle has a downwardly inclinedbranch port 32 feeding into a sleeve 33 threaded into the nozzle as at34. The sleeve is formed with two downwardly presented passages 35 andhas a screw 36 threaded thereinto, the screw being operable for coveringand uncovering the passages 35 to a desired extent.

I claim:

1. A pump for molten lead comprising a generally cylindrical housinghaving a pair of fixed brackets projecting therefrom intermediate thelength thereof, the brackets being adapted for resting on the rim of apot having a body of molten lead therein to support the housingvertically within the pot, and the portion of the housing below thebrackets being dimensioned to extend downwardly to a level near thebottom of the pot so as to be submerged in the molten lead, a rigid armprojecting from the submerged portion of the cylinder in an upwardlyinclined direction and having a nozzle at the upper end thereof abovethe level of the molten lead, a plunger reciprocable in the lower end ofthe housing and projecting upwardly above the housing and having ahandle at the upper end thereof, a pair of wings projecting from theplunger intermediate the upper end of the housing and the handle, anoperating lever engaging between the wings for reciprocating theplunger, the arm having a port leading from the lower end of the housingto the nozzle, a closure for the bottom end of the housing, and anintake valve mounted within said closure.

2. A pump for molten lead comprising a generally cylindrical housinghaving a pair of fixed brackets projecting sidewise therefromintermediate the length thereof, the brackets being adapted for restingon the rim of a pot having a body of molten lead therein to support thehousing vertically within the pot, and the portion of the housing belowthe brackets being dimensioned to extend downwardly to a level near thebottom of the pot so as to be submerged in the molten lead, a rigid armprojecting from the submerged portion of the cylinder in an upwardlyinclined direction and having a nozzle at the upper end thereof abovethe level of the molten lead, a plunger reciprocable in the lower end ofthe housing and having a handle at the upper end thereof, a pair ofwings projecting from the plunger intermediate the upper end of thehousing and the handle, an operating lever engaging between the wingsfor reciprocating the plunger, the arm having a port leading from thelower end of the housing to the nozzle, a closure for the bottom end ofthe housing, and an intake valve mounted within said closure, the armhaving an outlet valve at the lower end of its port.

ARTHUR L. GAGNE.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 625,998 Bancroft May 30, 1899 674,374 Bancroft May 21, 1901720,714 Lightbown Feb. 17, 1903 964,677 Nicholas et al July 19, 19101,149,285 Pierpont Aug. 10, 1915 1,193,859 Bary Aug. 8, 1916 1,226,408Tenca May 15, 1917 1,732,075 Willis Oct. 15, 1929 1,773,799 TornbergAug. 26, 1930 2,236,212 Huck Mar. 25, 1941 2,243,293 Stahl May 27, 19412,422,990 Spaier June 24, 1947 2,522,866 Gash Sept. 19, 1950 2,531,290Narrow Nov. 21, 1950 2,582,137 Kux Jan. 8, 1952 2,609,575 Morin Sept. 9,1952

